Method of making a perforate wafer from filamentary material

ABSTRACT

The invention includes a method of winding thin glass tubing or the like on a drum by blowing air against the end turn. This packs the turns tightly together. It has not heretofore been possible to do so because of the very thin and tenuous character of the tubing. The tubing is cut from the drum, laminated, bonded, and sliced perpendicular to the tubing axes. The result is a perforate wafer which may be used as a channel-type electron multiplier when a type of glass tubing is used which will produce a secondary emission ratio greater than unity from the interior surface of the tubing.

United States Patent [191 Uncapher 1 METHOD OF MAKING A PERFORATE WAFER FROM FILAMENTARY MATERIAL [75] Inventor: Richard Danby Uncapher, San

Fernando, Calif.

[73] Assignee: International Telephone and Telegraph Corporation, New York, N.Y.

[22] Filed: Nov. 1, 1968 [21] Appl. No.: 772,525

Field of Search 156/174, 175, 181, 182, 156/256, 296

[56] References Cited UNITED STATES PATENTS 3,268,312 8/1966 Grant 156/296 X Mar. 11, 1975 Ward et al. 156/296 X Goodrich et a1 313/103 ABSTRACT The invention includes a method of winding thin glass tubing or the like on a drum by blowing air against the end turn. This packs the turns tightly together. It has not heretofore been possible to do so because of the very thin and tenuous character of the tubing. The tubing is cut from the drum, laminated, bonded, and sliced perpendicular to the tubing axes. The result is a perforate wafer which may be used as a channel-type electron multiplier when a type of glass tubing is used which will produce a secondary emission ratio greater than unity from the interior surface of the tubing.

7 Claims, 6 Drawing Figures PATENTED 1 1975 [ATHE- METHOD OF MAKING A PERFORATE WAFER FROM FILAMENTARY MATERIAL BACKGROUND OF THE INVENTION This invention relates to a process of winding a flexible member on a cylindrical drum and, more particularly, to a method of winding a filamentary fiber or the like.

In the past, it has been the practice to wind a stringlike material on a drum in the shape of a helix. Mechanical means are employed to pack the helix turns tightly together. However, it is often very difficult to pack the turns because they are easily broken by physical contact with a tool. This is especially true of very thin filamentary materials.

SUMMARY OF THE INVENTION In accordance with the method of the present invention, the above-described and other disadvantages of the prior art are overcome by training a blast of air onto the helix turns as they are being wound. Contact with a solid object and breakage of the turns is thus eliminated.

It is a feature of the method of the present invention that it may be used to make an extremely wide variety of products. For example, by winding certain glass tubing, cutting, laminating, and cutting again, as will be described, it is possible to make channel-type electron multipliers of the type disclosed in US. Pat. No. 3,327,151. The construction and operation of these devices is also explained in Review of Scientific Instruments by G. W. Goodrich and W. C. Wiley, 1962, Vol. 33, page 761, and explained in Electronic Engineering by J. A. Adams and B. W. Manley, 1965, page 108M181.

It is also a feature of the method of the present invention that devices made thereby as described herein may be used in fiber optics. For example, they may be used as face plates for transmitting an image from one plane to another.

A further feature of the invention is that devices made thereby may be employed as blood filters and as flow collimators.

The above-described and other advantages of the invention will be better understood from the following description when considered in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings, which are to be regarded as merely illustrative:

FIG. 1 is a diagramatic view of an apparatus which may be employed to practice the method of the invention;

FIG. 2 is a perspective view illustrating another step of the method of the invention;

FIG. 3 is a perspective view of a set of glass tubes constructed in accordance with the invention;

FIGS. 4 and 5 are perspective views of laminated sheets of glass tubes; and

FIG. 6 is a perspective view of a perforated wafer constructed in accordance with the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT In the drawings, in FIG. 1, a drum 10 is rotated by a lathe 11. Glass tubing 12 is fed onto drum 10. Drum 10 is moved axially to the right, and tube 12 is threaded onto drum 10 in a shape of a helix at 13. The air nozzle 14 directs a blast of air against tubing 12 approximately at its initial point of contact of drum 10. A source of air 15 supplies air to nozzle 14.

When helix 13 has been wound as shown in FIG. 2, a portion of each turn thereof is bonded to an adjacent portion by lacquer at 16. Alternatively, the turns may be fused together by heat. The helix 13 is then cut apart at 17 midway in the area of bonding at 16. The turns of the helix are then layed out straight on a flat surface as indicated at 18 in FIG. 3. The straightened turns are then bonded together by lacquer or fusing. Alternatively, the entire helix on drum l2 may be lacquered or fused.

Sheet 18 is then cut into sections. These sections may be 6 X 1 inch. The tubing holes may appear at the end of the sections having the 1 inch dimension. The pieces are then stacked together as shown in FIG. 4 or in FIG. 5 to form a block 6 X l X 1 inch with all the holes in the tubing being located on the external surface thereof having a dimension of l X 1 inch. The laminated body is then cut perpendicularly to the tube axes. However, the laminates are bonded together by lacquer or fusing before the transverse cut is made. After the transverse cut is made, the wafer may have the appearance shown at 19 in FIG. 6. However, the number of holes has been reduced; and the size of the holes has been increased substantially for clarity.

In accordance with the foregoing, the use of the blast of air on drum 10 makes it possible to pack the turns of the helix tightly. This was not possible in the prior art where tools were used to pack the turns.

Note will be taken that the glass tubing 12 may have an outside diameter of 0.001 inch. This is about one third of the thickness of a human hair. In the prior art, it was thus impossible to pack filamentary material because it would break.

In accordance with the foregoing, wafer 19 may be employed as a channel-type electron multiplier if appropriate glass is employed. Lead glass is often employed.

Notwithstanding the foregoing, as stated previously, wafer 19 may be used as a face plate or other device in the fiber optics field. It also may be employed as a blood filter or flow collimator.

The invention is also applicable to wind any filamentary material that is flexible. The filamentary material may be hollow tubing, solid tubing, braided cable, or otherwise. The invention is applicable to, but not limited to, the use of materials such as glass, fiberglass, and plastic.

In winding, the filamentary material may be moved and the air blast may be moved instead of the drum.

Many other changes or modifications of the invention will suggest themselves to those skilled in the art. The invention is, therefore, not to be limited to the embodiment selected for this disclosure, the true scope of the invention being defined only in the appended claims.

What is claimed is:

1. The method of making a perforate wafer, said method comprising the steps of: laying a thin flexible tube on a drum, rotating the drum, and simultaneously moving it axially to wind said tube in a helix on said drum; blowing the last turn being wound approximately at its initial point of contact with the drum against the next turn adjacent thereto; cutting each turn of said tube off of said drum by cutting each turn in a direction approximately perpendicularly to the tube axis and along a line extending lengthwise along the drum axis; laying the severed turns flat in predetermined positions such that each severed turn has a surface contiguous to the other severed turns immediately adjacent thereto, each severed turn being contiguous to at least one other severed turn, all the axes of said severed turns being substantially parallel and lying in a single plane; bonding the most contiguous surfaces of each severed turn to the other contiguous surfaces of the others contiguous thereto in said predetermined positions; cutting said bonded turns perpendicularly to the axes thereof to provide smaller sheet-like sections, each section having a set of parallel tube axes; bonding the said sections together into a laminate in a manner such that a plane through all the tube axes of one section is substantially parallel to each corresponding plane through the axes of the other sections, all of said tube axes being parallel; cutting said laminate in a direction transverse to said tube axes to provide thin wafers, said wafers being perforate by virtue of the holes in the severed tubing.

2. The invention as defined in claim 1, wherein said tube is made of glass.

3. The invention as defined in claim 1, wherein said tube is made of fiberglass.

4. The invention as defined in claim 1, wherein said sections are stacked for bonding in positions such that the first set of parallel planes extend through a plurality of said sets of axes, respectively, a second set of parallel planes perpendicular to said first set also extend through different respective sets of tube axes.

5. The invention as defined in claim 4, wherein each of said second set of planes lying on one-half the number of tube axes that each of said first set does.

6. The invention as defined in claim 5, wherein all of the planes in said first set being equally spaced, all of the planes in said second set being equally spaced.

7. The invention as defined in claim 4, wherein each of said second set of planes lies in a number of tube axes equal to that on which each of said first set of planes lies. 

1. The method of making a perforate wafer, said method comprising the steps of: laying a thin flexible tube on a drum, rotating the drum, and simultaneously moving it axially to wind said tube in a helix on said drum; blowing the last turn being wound approximately at its initial point of contact with the drum against the next turn adjacent thereto; cutting each turn of said tube off of said drum by cutting each turn in a direction approximately perpendicularly to the tube axis and along a line extending lengthwise along the drum axis; laying the severed turns flat in predetermined positions such that each severed turn has a surface contiguous to the other severed turns immediately adjacent thereto, each severed turn being contiguous to at least one other severed turn, all the axes of said sevEred turns being substantially parallel and lying in a single plane; bonding the most contiguous surfaces of each severed turn to the other contiguous surfaces of the others contiguous thereto in said predetermined positions; cutting said bonded turns perpendicularly to the axes thereof to provide smaller sheet-like sections, each section having a set of parallel tube axes; bonding the said sections together into a laminate in a manner such that a plane through all the tube axes of one section is substantially parallel to each corresponding plane through the axes of the other sections, all of said tube axes being parallel; cutting said laminate in a direction transverse to said tube axes to provide thin wafers, said wafers being perforate by virtue of the holes in the severed tubing.
 1. The method of making a perforate wafer, said method comprising the steps of: laying a thin flexible tube on a drum, rotating the drum, and simultaneously moving it axially to wind said tube in a helix on said drum; blowing the last turn being wound approximately at its initial point of contact with the drum against the next turn adjacent thereto; cutting each turn of said tube off of said drum by cutting each turn in a direction approximately perpendicularly to the tube axis and along a line extending lengthwise along the drum axis; laying the severed turns flat in predetermined positions such that each severed turn has a surface contiguous to the other severed turns immediately adjacent thereto, each severed turn being contiguous to at least one other severed turn, all the axes of said sevEred turns being substantially parallel and lying in a single plane; bonding the most contiguous surfaces of each severed turn to the other contiguous surfaces of the others contiguous thereto in said predetermined positions; cutting said bonded turns perpendicularly to the axes thereof to provide smaller sheet-like sections, each section having a set of parallel tube axes; bonding the said sections together into a laminate in a manner such that a plane through all the tube axes of one section is substantially parallel to each corresponding plane through the axes of the other sections, all of said tube axes being parallel; cutting said laminate in a direction transverse to said tube axes to provide thin wafers, said wafers being perforate by virtue of the holes in the severed tubing.
 2. The invention as defined in claim 1, wherein said tube is made of glass.
 3. The invention as defined in claim 1, wherein said tube is made of fiberglass.
 4. The invention as defined in claim 1, wherein said sections are stacked for bonding in positions such that the first set of parallel planes extend through a plurality of said sets of axes, respectively, a second set of parallel planes perpendicular to said first set also extend through different respective sets of tube axes.
 5. The invention as defined in claim 4, wherein each of said second set of planes lying on one-half the number of tube axes that each of said first set does.
 6. The invention as defined in claim 5, wherein all of the planes in said first set being equally spaced, all of the planes in said second set being equally spaced. 